1. Field of the Invention
The present invention relates to an instrument guide for guiding a surgical instrument into a patient.
2. Prior Art
There have been developed various procedures to perform minimally invasive surgery. For example, there have been developed minimally invasive procedures to perform a coronary artery bypass graft (CABG). The minimally invasive CABG procedure can be performed with a robotic system sold by Computer Motion, Inc., the assignee of the present invention, under the trademark ZEUS.
The ZEUS system includes a plurality of robotic arms that can control the movement of surgical instruments inserted through small incisions in the patient. The surgical instruments move in accordance with the movement of handles held by a surgeon. The handles are located at a console that allows the surgeon to view a monitor that is coupled to an endoscope inserted into the patient. The surgeon can perform a surgical procedure by moving the handles and viewing the surgical site displayed by the monitor.
Performing a minimally invasive procedure may require a number of different surgical instruments. Each robotic arm of the ZEUS system has a coupling mechanism that allows instruments to be attached to, and detached from, the arm. The surgeon, or a surgeon assistant can readily replace instruments during a procedure.
The instruments are typically inserted through a trocar that penetrates the body cavity of the patient. The ZEUS system utilizes the incision point of the patient as a pivot point for the robotic arm and the surgical instrument. The system utilizes a software routine that transforms the coordinates of the surgical instruments to stationary world coordinates to provide commands that accurately move the instruments.
An instrument guide may be placed within the trocar to guide the instrument, maintain robotic arm positioning and facilitate instrument exchanges during surgery. The inner diameter of the instrument guide has approximately the same diameter as the outer diameter of the surgical instrument to prevent relative radial movement between the instrument and the guide. Any excessive space between the surgical instrument and the instrument guide may result in a lag between the movement of the handles and the movement of the instrument. This lag may increase the complexity of performing the procedure.
The outer diameter of the surgical instruments may vary from instrument to instrument. Smaller surgical instruments may create an undesired space between the instrument and the guide. It would be desirable to provide an instrument guide that can be secured to a variety of surgical instruments each having a different outer diameter.
One embodiment of the present invention is an instrument guide that can be inserted into a patient and guide a surgical instrument. The instrument guide includes a shaft that has an inner channel adapted to receive the surgical instrument. The guide also has a leaf that extends from the shaft. The leaf is adapted to move relative to the shaft when the surgical instrument is inserted into the inner channel.